1. Technical Field
The present invention relates generally to access points used in wireless local area networks, and-more specifically to an access point which includes multiple wireless adapters.
2. Related Art
Wireless local area networks (WLAN's) use radio frequency transmissions to communicate between roaming computer devices and access points (or base stations). The access points are connected to an infrastructure that electronically connects all of the access points to a host system. The wired infrastructure and the access points make up an information distribution network used for the transfer of information and for communications.
In a wireless networking environment, various types of devices may need to communicate within a given area When incompatibilities between device types arise, the wireless infrastructure must accommodate the various device types. Accommodating the different device types in a single infrastructure is generally difficult to accomplish. Further, devices within the wireless networking environment typically communicate differing types of data, each with its own priority and bandwidth requirements. Accommodating the various types of data with their related priorities often could not be accomplished by prior devices due to bandwidth limitations, conflicting priorities and incompatible standards within the wireless network.
In prior WLANs, a first wireless terminal that desired to communicate with a base station often could not detect transmissions from a second wireless terminal currently engaged in ongoing communication with the access point. As a result, the wireless terminal often initiated transmissions that collided with the ongoing communications. Operation of this type is referred to as a “hidden terminal” situation. To solve the hidden terminal situation, some prior base stations were configured with a second transmitter for delivering a carrier signal on a “busy channel” whenever the base station was engaged in communication on the “data channel.” All terminals were also fitted with a second receiver, tuned to the busy channel, and required to check the busy channel before initiating communication on the data channel. However, the additional power required, bandwidth used, hardware needed and associated cost made the busy channel solution undesirable for most applications.
Some prior WLANs attempted to solve operational difficulties by simply increasing the transmission capacity available on the infrastructure. Such expansion temporarily decreased conflicts in operation of the WLANs. However, the infrastructure, which is expensive to install, typically became overloaded quickly resulting in the same or similar problems.